Growth Curve Fitting And Performance Analysis Of Jiangquan Black Pigs And Yimeng Black Pigs

As an important genetic resource in Shandong Province,the growth curve fitting of Jiangquan black pigs and Yimeng black pigs has not been reported.In order to study the growth and development of Jiangquan black pigs and Yimeng black pigs in different periods,and to provide reference for their scientific breeding,seed preservation,development and utilization.In this study,120 healthy and stable experimental pigs were selected,including 60 Jiangquan black pigs and 60 Yimeng black pigs each,and the two breeds were 30 boars and30 sows.In 15 d as a period of measurement,Body Weight(BW),Backfat thickness(BFT),Body length(BL),Chest circumference(CC),Abdominal circumference(AC),Body height(BH)and Deep Chest(DC)were measured at the age of 60 ～ 240 days,using 3 nonlinear regression models(Logistic model,Gompertz model and Von Bertalanffy model)curve fitting the growth trait and body ruler trait respectively,explores the optimal model,compares the differences between the thickness of pigs of different breeds and genders,and analyzes the correlation of each measurement of daily age and weight.And analyze the correlation between weight and body ruler traits and establish a regression model of weight and body ruler.The research results are as follows:1.Curve fitting of growth traits: The research results show that the fitting degree of the three models is above 0.992,and the fitting degree is good.Among them,the Von Bertalanffy model fitting results are the best,and the fitting degrees are: Jiangquan black pigs 0.997,Yimeng black pigs 0.999.The inflection point of Yimeng black pigs is the earliest(101.74 d),and the inflection point of Jiangquan black pigs is the latest(115.38 d).2.Curve fitting of body ruler traits: The research results show that the fit of the three models is above 0.991,and the fit is good.Among them,the fit result of the Logistic model is the best.The fit of the Jiangquan black pigs and Yimeng black pigs is more than 0.994,and the fit of the chest circumference is above.Above 0.995,the abdominal circumference fitting degree is more than 0.993,the body height fitting degree is more than 0.993,and the deep chest fitting degree is more than 0.991.The inflection point of each body ruler is the earliest appearance of Yimeng black pig sow,and Jiangquan black pig is the latest.3.Comparative analysis of the back thickness of pigs of different breeds and genders: in the same breed,the live back thickness of pigs of different sex pigs is slightly smaller than that of sows,and the difference in the live back thickness of each measurement of daily-aged male sows is not significant(P > 0.05).For different breeds,the live back thickness of pigs of the same sex pig is higher than that of Jiangquan black pigs,and at the age of 165 days,the back thickness of Yimeng black pigs is significantly larger than that of Jiangquan black pigs(P < 0.05).4.Correlation between different measurements of daily age weight: there is a large correlation between the different daily age weights of Jiangquan black pigs and Yimeng black pigs.The correlation coefficient is above 0.75,and the correlation coefficient has reached a very significant level(P < 0.01).5.Regression analysis of weight and body ruler: The research results show that the weight and body length,chest circumference,body height and chest depth of Jiangquan black pigs boar are optimal in the cubic model,the weight and abdominal circumference are optimal in the cubic model and quadratic model,and the weight and body length,chest circumference,abdominal circumference,body height and deep chest in Jiangquan The boar’s weight and body length,chest circumference,abdominal circumference and body height are the best in the cubic model,and the weight and deep chest are the best in the power model;the weight and body length and weight and chest in Yimeng black pigs is the best in the cubic model,the weight and abdominal circumference and weight and deep chest are the best in the power model,.It provides a reference for the weight estimation of Jiangquan black pig and Yimeng black pig group.As a new pig breed cultivated by Yimeng black pig and Duroc,Jiangquan black pigs not only retains the excellent characteristics of Yimeng black pig’s resistance to coarse feeding and strong disease resistance,but also accelerates the growth rate to a certain extent,reduces the thickness of the living body’s back,and increases the number of live larvae,making Jiangquan The growth characteristics and body ruler traits of Jiangquan black pigs are quite different from those of Yimeng black pigs.The main manifestation is that the weight and body ruler of the daily-aged Jiangquan black pigs are higher than that of Yimeng black pigs.Both Jiangquan black pigs and Yimeng black pigs show the growth and development of bone first,then muscle and finally fat deposition.